Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and idempotentHint=true, but the description goes far beyond by explaining the actual content and behavior: passenger names, accommodation class, citizenship, destination, fare, fare_surge range (0.6x–2.0x), market condition dynamics, and a conditional transit_lounge section. This adds substantial context about what the tool returns and how to interpret it, with no contradictions.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is front-loaded with the core action and then provides dense but relevant details about the output. It is long and uses complex sentences, but every piece (passenger info, fare surge, market conditions, transit lounge) is necessary for a tool with no output schema. Minor structural improvements could help readability, but it remains appropriately sized.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description carries full responsibility for explaining the return value. It thoroughly covers all major output elements: passenger details, destination, fare, fare_surge, demand_level, market_conditions, and transit_lounge. The tool is simple (one parameter) and the description leaves no critical gaps.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The only parameter session_id has 100% schema description coverage, so the schema already documents meaning. The description does not add any parameter-specific semantics, but since coverage is high, the baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses a specific verb and resource: 'List citizens waiting for transport at your current station,' clearly distinguishing it from broader tools like list_passengers. It details exactly what is shown (passenger info, destination, fare) and includes the prerequisite 'You must be docked,' making the purpose unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly states the condition 'You must be docked' and provides a direct use case: 'use this to decide which destinations to load with load_passenger.' It names the sibling tool load_passenger as the next step, giving clear context for when to use this tool, though it does not explicitly mention when not to use it or contrast with list_passengers.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.